Ghost cell odontogenic carcinoma arising in dentinogenic ghost cell tumor,peripheral: A case report

Ghost cell odontogenic carcinoma (GCOC) is an extremely rare intraosseous malignant odontogenic tumor with prominent ghost cell keratinization and dentinoid formation. Here, we present the first case of GCOC arising in dentinogenic ghost cell tumor (DGCT), peripheral. The patient was a man in his 60s with an exophytic mass in the anterior part of lower gingiva. The resected tumor measured 4.5 cm in maximum diameter. Histologically, the nonencapsulated tumor proliferated in the gingiva without bone invasion. It was predominantly composed of ameloblastoma-like nests and islands of basaloid cells with ghost cells and dentinoid in the mature connective tissue, suggesting DGCT, peripheral. As minor components, sheets of atypical basaloid cells and ameloblastic carcinoma-like nests with pleomorphism and high proliferative activity (Ki-67 labeling index up to 40%) consistent with malignancy were identified. CTNNB1 mutation and β-catenin nuclear translocation were observed in both benign and malignant components. Final diagnosis was GCOC arising in DGCT, peripheral. GCOC shows similar histological features to DGCT. In this unique case without invasion, the cytological atypia and high proliferative activity supports the diagnosis of malignant transformation from DGCT.     

A case of intestinal malrotation apparent after laparoscopically total proctocolectomy followed by ileal-pouch-anal anastomosis for ulcerative colitis

Intestinal malrotation (IM) is an abnormality due to a failure of the normal midgut rotation and fixation. We report a case of 46-year-old man with ulcerative colitis whose IM was apparent after laparoscopically total proctocolectomy (TPC) followed by ileal-pouch-anal anastomosis (IPAA) and ileostomy. There was no abnormal anatomy except for mobile cecum/ascending colon during the initial operation. Intestinal obstruction occurred after ileostomy closure. The computed tomography scan showed the duodeno-jejunal transition was located in right abdomen, the superior mesenteric vein was located left of the superior mesenteric artery (SMA) and the obstruction point was the distal ileum near the pouch. We performed an ileo-ileo bypass across the ventral side of the SMA to relieve the intestinal obstruction. The patient would have incomplete IM preoperatively, which became apparent by TPC. In case of TPC for mobile colon, anatomy of small intestine should be checked before IPAA.     

A rare brainstem hemorrhage due to incomplete transvenous embolization of the cavernous sinus dural arteriovenous fistula: A case report

Endovascular embolization is generally thought to be safe and effective for the cavernous sinus dural arteriovenous fistula (CS DAVF); however, some complications have been reported. We report an extremely rare brainstem hemorrhage associated with transvenous embolization (TVE) of CS DAVF. A 66-year-old man presented with right-sided conjunctival chemosis and exophthalmos. His brain magnetic resonance image showed right CS DAVF. Thus, emergent TVE was performed. Although his symptoms improved after the first TVE, magnetic resonance image showed brainstem edema, and venous congestion was suspected because of incomplete TVE. Second TVE was performed. Thereafter, computed tomography showed brainstem hemorrhage, resulting in the occurrence of right abducent nerve palsy, right-sided facial palsy, and ataxia. The patient''s condition gradually improved, and a year has passed without recurrence. Incomplete TVE of CS DAVF can result in life-threatening complications, such as cerebral hemorrhage. To avoid these complications, the anatomical structure of the cavernous sinus should be understood accurately, and important drainage veins should be determined.     

A case of subdural hemorrhage due to ruptured cerebral aneurysm presenting with atypical imaging features

Acute subdural hemorrhage caused by ruptured cerebral aneurysms is rare. Herein, we report an atypical case of subdural hemorrhage caused by ruptured anterior communicating artery aneurysm in a 49-year-old woman. Computed tomography revealed subarachnoid, intracerebral, and subdural hemorrhages. After the treatment with endovascular coiling significantly decreased the patient''s subdural hemorrhage. However, the subdural hemorrhage revealed and became iso-attenuation compared with the white matter on the 11th day, and hypo-attenuation on the 19th day. On the 33rd day, this subdural hemorrhage completely resolved after discontinuation of dual antiplatelet therapy. Due to rapid changes in the radiologic features of SDH, frequent computed tomography scans at least once a week may be needed especially in patients who receive antiplatelet therapy during the vasospasm phase.     

Definitive engagement of cytotoxic CD8 T cells in C protein–induced myositis,a murine model of polymyositis

Objective

To substantiate a pathogenic role of cytotoxic CD8 T cells in the development of a murine polymyositis model, C protein–induced myositis (CIM).

Methods

Beta₂‐microglobulin–null mutant, perforin‐null mutant, and wild‐type (WT) C57BL/6 mice were immunized with skeletal muscle C protein fragments to provoke CIM. Regional lymph node CD8 or CD4 T cells stimulated with C protein–pulsed dendritic cells were transferred adoptively to naive mice. Inflammation and damage of the muscle tissues were evaluated histologically.

Results

The incidence of myositis development was significantly lower in β₂‐microglobulin–null and perforin‐null mutant mice compared with WT mice. Inflammation was less severe in mutant mice, and the incidence of muscle injury was reduced significantly. Adoptive transfer of lymph node T cells from mice with CIM induced myositis in naive recipient mice. The CD8 T cell–induced muscle injuries were significantly more severe than the CD4 T cell–induced muscle injuries.

Conclusion

Perforin‐mediated cytotoxicity by CD8 T cells is definitively responsible for muscle injury in CIM.